diff --git a/Shorewall/lib.core b/Shorewall/lib.core
index e8dbb21ad..660143cf7 100644
--- a/Shorewall/lib.core
+++ b/Shorewall/lib.core
@@ -176,8 +176,24 @@ interface_is_up() {
 #
 interface_is_usable() # $1 = interface
 {
-    [ "$1" = lo -o $COMMAND = enable ] && return 0
-    interface_is_up $1 && [ "$(find_first_interface_address_if_any $1)" != :: ] && run_isusable_exit $1
+    local status;
+    status=0
+
+    if [ "$1" != lo ]; then
+	if [ $g_family -eq 4 ]; then
+	    if interface_is_up $1 && [ "$(find_first_interface_address_if_any $1)" != 0.0.0.0 -a "$COMMAND" != enable ]; then
+		run_isusable_exit $1
+		status=$?
+	    fi
+	else
+	    if interface_is_up $1 && [ "$(find_first_interface_address_if_any $1)" != :: -a "$COMMAND" != enable ]; then
+		run_isusable_exit $1
+		status=$?
+	    fi
+	fi
+    fi
+
+    return $status
 }
 
 #